• Journal of Industrial Technology
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• v.27 no.A
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• pp.61-67
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• 2007

The construction machine is the composite machine assembled by about 30,000 parts. Excavator, one kind of a construction machine, plays the leading role for export of construction equipment. It is generally impossible to produce all of the items within one company. Especially the supply of hydraulic control valves, one of the core part of the construction equipment, depends on the import heavily. So it is important to make an efficient production plan of hydraulic control valves in the company. The most important thing for the production scheduling of a hydraulic control valve is to make production schedule keeping the start date for assembly line for an excavator and to make minimization of the stock level. The production plan of hydraulic control valve includes the decision of the quantity supplied by subcontractor. This paper presents a scheme for a scheduling system of the hydraulic control valve considering the schedule of the assembly line for excavator production. This paper provides a methodology, which can make a plan of supply and production and generate a detailed schedule for daily production.

• Proceedings of the Korean Institute Of Construction Engineering and Management
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• autumn
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• pp.454-457
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• 2001

All of the partner must manage continually scheduling for the successful project in construction. Besides, that is not a important only contracter's managing but also owner's managing which is a very important about project finishing in time. Especially, in the case of mega project, the owner has to manage progress of scheduling to control contractor. And the case of progress to delay or to change, owner, contractor, and inspector must make a plan of recovery scheduling. This study proposes a construction process model from IDEF Methodology.

• International conference on construction engineering and project management
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• 2015.10a
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• pp.169-173
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• 2015

The linear scheduling method or line-of-balance (LOB) is a popular choice for projects that involve repetitive tasks during project execution. The method, however, produces deterministic schedule that does not convey a range of potential project outcomes under uncertainty. This results from the fact the basic scheduling parameters such as crew production rates are estimated to be deterministic based on single-point value inputs. The current linear scheduling technique, therefore, lacks the capability of reflecting the fluctuating nature of the project operation. In this paper the authors address the issue of how the variability of operation and production rates affects schedule outcomes and show a more realistic description of what might be a realistic picture of typical projects. The authors provide a solution by providing a more effective and comprehensive way of incorporating the crew performance variability using a Monte Carlo simulation technique. The simulation outcomes are discussed in terms of how this stochastic approach can overcome the shortcomings of the conventional linear scheduling technique and provide optimum schedule solutions.

• Korean Journal of Construction Engineering and Management
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• v.6 no.1 s.23
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• pp.73-79
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• 2005

This paper, introduces a Stochastic Project Scheduling Simulation system (SPSS III) developed by the author to predict a project completion probability in a certain time. The system integrates deterministic CPM, probabilistic PERT, and stochastic Discrete Event Simulation (DES) scheduling methods into one system. It implements automated statistical analysis methods for computing the minimum number of simulation runs, the significance of the difference between independent simulations, and the confidence interval for the mean project duration as well as sensitivity analysis method in What-if analyzer component. The SPSS 111 gives the several benefits to researchers in that it (1) complements PERT and Monte Carlo simulation by using stochastic activity durations via a web based JAVA simulation over the Internet, (2) provides a way to model a project network having different probability distribution functions, (3) implements statistical analyses method which enable to produce a reliable prediction of the probability of completing a project in a specified time, and (4) allows researchers to compare the outcome of CPM, PERT and DES under different variability or skewness in the activity duration data.

• International conference on construction engineering and project management
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• 2007.03a
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• pp.739-748
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• 2007

The objective of this research study is to develop the permutation-based genetic algorithm for solving the resource-constrained project scheduling problem in construction engineering by incorporating elitism into genetic algorithm. A key aspect of the algorithm was the development of the elitist roulette selection operator to preserve the best individual solution for the next generation so the improved solution can be obtained. Another notable characteristic is the application of the parallel schedule generation scheme to generate a feasible solution to the problem. Case studies with a standard test problem were presented to demonstrate the performance and accuracy of the algorithm. The computational results indicate that the proposed algorithm produces reasonably good solutions for the resource-constrained project scheduling problem.

• Korean Journal of Construction Engineering and Management
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• v.5 no.2 s.18
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• pp.211-218
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• 2004

In a large owner organization, a program manager of multiple maintenance and remodeling projects has experienced increasing scale and complexity of coordinating the M/R projects with in-house technicians who belong to multiple trade shops. This paper proposes a dual-level hierarchical planning strategy that consists of a program master plan in the long-term horizon and a master construction schedule in an operational scheduling window. A rolling horizon approach to the program master plan is proposed to deal with the external uncertainty of unknown stream of project requests. A resource-constrained scheduling algorithm is developed to generate the master construction schedule in a scheduling window. During development of the algorithm, more emphasis is placed on long-term organizational resource continuity, especially flow management of program constraint resources, than ephemeral events of an individual activity and project. Monte Carlo simulation experiments of three scheduling windows are used to evaluate the relative performance of the proposed scheduling algorithm against three popular scheduling heuristics for resource-constrained multiple projects.

• International conference on construction engineering and project management
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• 2022.06a
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• pp.1241-1241
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• 2022

In the current construction industry, difficulty arises in creating an adequate baseline schedule to establish a fundamental plan for construction. This presentation will present the research findings which investigated industry-recognized schedule metrics that aid in the successful implementation of said schedule. Industry organizations (Association for the Advancement of Cost Engineering, the Government Accountability Office, the Project Management Institute, and local city, state, and county government offices) provide standardized guidelines with specific metrics requirements to ensure successful implementation. However, most of those metrics are substantiated or validated in their effectiveness. The study examined the impact between these industry-recognized critical metrics and three distinct scheduling characteristics: Project Type, Project Duration, and Project Density (number of activities within a schedule). The research results showed that, among the 12 various schedules evaluated in parallel with 20 industry-recognized critical metrics, seven metrics substantially demonstrate a significant impact on a project schedule's success. Furthermore, six of the seven metrics directly correlate to at least one of the three scheduling characteristics outlined. As a result, this research has established more predictable outcomes based on impacts between three distinct project characteristics and 20 of the most discussed/researched critical scheduling metrics in the field. This allows management teams to have more confidence in establishing critical milestones and accurate turnover dates from the start of the project through its final completion.

• Proceedings of the Korean Operations and Management Science Society Conference
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• 1995.04a
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• pp.758-759
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• 1995

In large-scale industry such as shipbuilding, aircraft manufacturing, and construction industry etc., it is required to consider two or three-dimensional spatial availability as one of bottlenecked resource constraints. We call this kind of scheduling a spatial scheduling, which considers the dynamic spatial layouts of objects as well as the traditional resource constraints. Since 1991, we have researched on the spatial scheduling for shipbuilding plant (Lee & Lee, 1992; Lee et al., 1994, Lee et al., 1995). In this paper, we present the various issues of spatial scheduling for the researchers and developers attacking spatial scheduling problems.

• Journal of the Korean Professional Engineers Association
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• v.33 no.3
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• pp.59-63
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• 2000

The purpose of this study is to understand the method of scheduling of Petronas twin tower project. Petronas twin tower is the highest building in the world today. Kuala Lumpur City Center Berhad which is owner of Petronas twin tower, managed this construction project by use of useful scheduling techniques, that is, milestone, NSC, NS, PDM, rolling wave, hammock. Now we consider this techniques and try to apply to our construction management.

• International conference on construction engineering and project management
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• 2007.03a
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• pp.777-786
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• 2007

This paper presents a modified simulated annealing algorithm to optimize linear scheduling projects with multiple resource constraints and its effectiveness is verified with a proposed problem. A two-stage solution-finding procedure is used to model the problem. Then the simulated annealing and the modified simulated annealing are compared in the same condition. The comparison results and the reasons of improvement by the modified simulated annealing are presented at the end.